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PURPOSE: Research supports physical activity as a method to heighten stress resistance and resilience through positive metabolic alterations mostly affecting the neuroendocrine system. High-intensity interval training (HIIT) has been proposed as a highly effective time-saving method to induce those changes. However, existing literature relies heavily on cross-sectional analyses, with few randomised controlled trials highlighting the necessity for more exercise interventions. Thus, this study aims to investigate the effects of HIIT versus an active control group on the stress response to an acute psychosocial stressor in emotionally impulsive humans (suggested as being strong stress responders). METHODS: The study protocol was registered online (DRKS00016589) before data collection. Sedentary, emotionally impulsive adults (30.69 ± 8.20 y) were recruited for a supervised intervention of 8 weeks and randomly allocated to either a HIIT (n = 25) or a stretching group (n = 19, acting as active controls). Participants were submitted to a test battery, including saliva samples, questionnaires (self-efficacy- and perceived stress-related), visual analogue scales (physical exercise- and stress-related), and resting electroencephalography and electrocardiography assessing their reaction to an acute psychological stressor (Trier Social Stress Test) before and after the exercise intervention. RESULTS: HIIT increased aerobic fitness in all participants, whereas stretching did not. Participants from the HIIT group reported perceiving exercising more intensively than those from the active control group (Æp2 = 0.108, p = 0.038). No further group differences were detected. Both interventions largely increased levels of joy post-TSST (Æp2 = 0.209, p = 0.003) whilst decreasing tension (Æp2 = 0.262, p < 0.001) and worries (Æp2 = 0.113, p = 0.037). Finally, both interventions largely increased perceived levels of general self-efficacy (Æp2 = 0.120, p = 0.029). CONCLUSION: This study suggests that 8 weeks of HIIT does not change the psychoneuroendocrine response to an acute psychological stress test compared to an active control group in emotionally impulsive humans. Further replications of supervised exercise studies highly powered with active and passive controls are warranted.
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OBJECTIVE: The human matrilin-3 T303M (in mouse T298M) mutation has been proposed to predispose for osteoarthritis, but due to the lack of an appropriate animal model this hypothesis could not be tested. This study was carried out to identify pathogenic mechanisms in a transgenic mouse line by which the mutation might contribute to disease development. METHODS: A mouse line carrying the T298M point mutation in the Matn3 locus was generated and features of skeletal development in ageing animals were characterized by immunohistology, micro computed tomography, transmission electron microscopy and atomic force microscopy. The effect of transgenic matrilin-3 was also studied after surgically induced osteoarthritis. RESULTS: The matrilin-3 T298M mutation influences endochondral ossification and leads to larger cartilage collagen fibril diameters. This in turn leads to an increased compressive stiffness of the articular cartilage, which, upon challenge, aggravates osteoarthritis development. CONCLUSIONS: The mouse matrilin-3 T298M mutation causes a predisposition for post-traumatic osteoarthritis and the corresponding knock-in mouse line therefore represents a valid model for investigating the pathogenic mechanisms involved in osteoarthritis development.
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Artrite Experimental/genética , Osteoartrite do Joelho/genética , Osteogênese/genética , Animais , Artrite Experimental/diagnóstico por imagem , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Cartilagem Articular/metabolismo , Cartilagem Articular/ultraestrutura , Colágeno/ultraestrutura , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Proteínas Matrilinas/genética , Meniscectomia , Meniscos Tibiais/cirurgia , Camundongos , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Mutação Puntual , Microtomografia por Raio-XRESUMO
BACKGROUND: About 10% of patients develop persistent symptoms after mild/moderate COVID-19. We have previously reported detection of antinuclear autoantibodies/extractable nuclear antigens (ANA/ENA) in patients with severe COVID-19. OBJECTIVES: The aim of this small pilot study was to characterize long-/post-COVID and to evaluate possible similarities between lung involvement in long-/post-COVID and connective tissue disease (CTD). METHODS: We prospectively enrolled 33 previously healthy patients with persistent pulmonal symptoms after mild/moderate COVID-19 without hospitalization (median age, 39â¯years). We performed clinical evaluation including pulmonary function tests, computed tomography (CT), and serology for ANA/ENA. In 29 of 33 patients, transbronchial biopsies (TBBs) were taken for histopathological assessment. RESULTS: Most patients presented with disturbed oxygen pulse in spiroergometry and slight lymphocytosis in bronchoalveolar lavage (BAL) fluid. The CT pattern showed bronchial wall thickening and increased low-attenuation volume. Autoantibodies were detected in 13 of 33 patients (39.4%). Histopathological assessment showed interstitial lymphocytosis with alveolar fibrin and organizing pneumonia. Ultrastructural analyses revealed interstitial collagen deposition. CONCLUSION: While histopathology of pulmonary long-/post-COVID alone is unspecific, the combination with clinical and radiological features together with detection of autoantibodies would allow for a diagnosis of interstitial pneumonia with autoimmune features (IPAF). Since we observe interstitial collagen deposition and since IPAF/CTD-ILD might progress to fibrosis, the persistence of autoantibodies and possible fibrotic change should be closely monitored in autoantibody-positive long-/post-COVID patients.
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COVID-19 , Doenças Pulmonares Intersticiais , Adulto , Humanos , Pulmão/diagnóstico por imagem , Projetos Piloto , SARS-CoV-2RESUMO
Chemotherapy-induced peripheral neuropathy (CIPN) is a prevalent and clinically relevant side effect of chemotherapy. The symptoms diminish patients' quality of life and represent a decisive limiting factor for medical therapy. To date, effective treatment options are lacking. Specific exercise interventions have proven promising to target relevant symptoms. We conducted a prospective, four-armed, randomized, controlled trial, to evaluate the effects of sensorimotor training (SMT) and whole-body vibration training (WBV) on patients with CIPN. Participants (N = 40) were randomized to either one of two intervention groups (SMT N = 10 or WBV N = 10) or oncological control group (N = 10) and matched by gender and age with a healthy control (N = 10). The intervention groups exercised twice a week for 6 weeks. Primary endpoint was the reduction of CIPN-related symptoms (improve peripheral deep sensitivity, Achilles tendon reflex (ASR) and patellar tendon reflex (PSR), light-touch perception, sense of position, and lower leg strength). Secondary endpoints were nerve conduction velocity and amplitude, balance control, quality of life, and CIPN-related pain. Patients exercising improved sensory and associated motor symptoms. Significant intergroup differences were found for the tendon reflexes (ASR P = .017 and PSR P = .020), peripheral deep sensitivity (P = .010), and pain (P = .043). Furthermore, tendencies were found regarding the subjective improvement of symptoms (P = .075) and two subscales of the EORTC-QLQ-C30 questionnaire: pain (P = .054) and dyspnea (P = .054). The results for the SMT group were superior regarding the tendon reflexes, and a tendency regarding the subjective report of symptoms, while WBV was superior regarding pain. SMT and WBV behold a large potential to reduce CIPN-related symptoms and can be considered feasible and safe for patients with CIPN (compliance 97.5%, no adverse events).Registration: DRKS00013027.
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Quimioterapia de Indução/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Qualidade de Vida/psicologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Inquéritos e Questionários , Resultado do Tratamento , VibraçãoRESUMO
Both hypoxia (decreased oxygen availability) and hyperoxia (increased oxygen availability) have been shown to alter exercise adaptations in healthy subjects. This review aims to clarify the possible benefits of exercise during short-term exposure to hypoxia or hyperoxia for patients with type 2 diabetes mellitus (T2DM). There is evidence that exercise during short-term exposure to hypoxia can acutely increase skeletal muscle glucose uptake more than exercise in normoxia, and that post-exercise insulin sensitivity in T2DM patients is more increased when exercise is performed under hypoxic conditions. Furthermore, interventional studies show that glycemic control can be improved through regular physical exercise in short-term hypoxia at a lower workload than in normoxia, and that exercise training in short-term hypoxia can contribute to increased weight loss in overweight/obese (insulin-resistant) subjects. While numerous studies involving healthy subjects report that regular exercise in hypoxia can increase vascular health (skeletal muscle capillarization and vascular dilator function) to a higher extent than exercise training in normoxia, there is no convincing evidence yet that hypoxia has such additive effects in T2DM patients in the long term. Some studies indicate that the use of hyperoxia during exercise can decrease lactate concentrations and subjective ratings of perceived exertion. Thus, there are interesting starting points for future studies to further evaluate possible beneficial effects of exercise in short-term hypoxia or hyperoxia at different oxygen concentrations and exposure durations. In general, exposure to hypoxia/hyperoxia should be considered with caution. Possible health risks-especially for T2DM patients-are also analyzed in this review.
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Diabetes Mellitus Tipo 2/terapia , Terapia por Exercício , Hiperóxia , Hipóxia , Glucose/metabolismo , Humanos , Resistência à Insulina , Ácido Láctico/sangue , Músculo Esquelético/fisiologia , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Cancer patients with bone metastases have previously been excluded from participation in physical activity programmes due to concerns of skeletal fractures. Our aim was to provide initial information on the association between physical activity levels and physical and mental health outcomes in prostate cancer patients with bone metastases. Between 2012 and 2015, 55 prostate cancer patients (mean age 69.7 ± 8.3; BMI 28.6 ± 4.0) with bone metastases (58.2% >2 regions affected) undertook assessments for self-reported physical activity, physical and mental health outcomes (SF-36), objective physical performance measures and body composition by DXA. Sixteen men (29%) met the current aerobic exercise guidelines for cancer survivors, while 39 (71%) reported lower aerobic exercise levels. Men not meeting aerobic exercise guidelines had lower physical functioning (p = .004), role functioning (physical and emotional) (p < .05), general health scores (p = .014) as well all lower measures of physical performance (p < .05). Lower levels of aerobic exercise are associated with reduced physical and mental health outcomes in prostate cancer patients with bone metastases. While previous research has focused primarily in those with non-metastatic disease, our initial results suggest that higher levels of aerobic exercise may preserve physical and mental health outcomes in prostate cancer patients with bone metastases. Clinical Trial Registry: Trial Registration: ACTRN12611001158954.
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Neoplasias Ósseas/fisiopatologia , Exercício Físico , Saúde Mental , Neoplasias da Próstata/fisiopatologia , Absorciometria de Fóton , Tecido Adiposo , Idoso , Composição Corporal , Neoplasias Ósseas/psicologia , Neoplasias Ósseas/secundário , Estudos Transversais , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Neoplasias da Próstata/psicologia , Papel (figurativo) , Autorrelato , Teste de CaminhadaRESUMO
Aim In Germany all childhood cancer patients and their families are offered the opportunity to participate in a four-week, family-oriented, inpatient rehabilitation program in order to facilitate (re-)integration into everyday life. The aim of this study is to evaluate the effect of this rehabilitation program on motor performance, quality of life (QoL) and fatigue. Methods Motor performance, QoL and fatigue were assessed in 22 childhood cancer patients and 20 healthy siblings at the beginning (t1) and the end (t2) of the four-week rehabilitation program, as well as 6 months later (t3). Results At t1 significant differences between groups were found in motor performance and physical well-being. Improvements in motor performance, QoL and fatigue were found in both groups. Conclusion Different preconditions must be considered. Childhood cancer patients as well as healthy siblings benefit from a family-oriented rehabilitation program.
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Terapia por Exercício/métodos , Fadiga/prevenção & controle , Fadiga/psicologia , Neoplasias/psicologia , Neoplasias/reabilitação , Desempenho Psicomotor , Qualidade de Vida/psicologia , Adolescente , Criança , Feminino , Humanos , Masculino , Resultado do TratamentoRESUMO
Metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) are associated with macro- and microcirculatory complications that reduce physical performance. Wearing compression garments to potentially optimize hemodynamics has been discussed. This study investigates the effects of wearing compression stockings on physical performance-related variables in type 2 diabetic men with metabolic syndrome (n=9, 57±12 years, BMI: 36±4 kg/m(2)). Participants served as their own controls in a randomized 3*3 crossover study wearing below-knee stockings with either compression (24 or 30 mmHg ankle pressure) or no compression. Venous pooling and lower limb oxygenation profiles were determined with near-infrared spectroscopy and arterial oxygen saturation was determined using a pulse oxymeter. Measurements were performed in the supine lying position, during standing, following 10 tiptoe exercises and after submaximal intensity cycling. In addition, lactate and erythrocyte deformability were analyzed in capillary blood pre- and post-exercise. Erythrocyte deformability was analyzed using a laser-assisted optical rotational red cell analyzer. No significant differences in any variables when wearing different compression or regular stockings were evident at any point of measurement. This study did not reveal any beneficial effects of wearing compression stockings at rest and during acute bouts of moderately intense exercise in this particular patient group.
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Diabetes Mellitus Tipo 2/terapia , Teste de Esforço , Hemodinâmica , Síndrome Metabólica/terapia , Meias de Compressão , Idoso , Estudos Cross-Over , Deformação Eritrocítica , Humanos , Ácido Láctico/sangue , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Oximetria , Consumo de Oxigênio , Descanso , Espectroscopia de Luz Próxima ao Infravermelho , Insuficiência Venosa/terapiaRESUMO
OBJECTIVES: The purpose of the present study was to evaluate the effects of superimposed electromyostimulation (E) during cycling on myokines and markers of muscle damage, as E might be a useful tool to induce a high local stimulus to skeletal muscle during endurance training without performing high external workloads. METHODS: 13 subjects participated in three experimental trials each lasting 60 min in a randomized order. 1) Cycling (C), 2) Cycling with superimposed E (C+E) and 3) E. Interleukin-6 (IL-6), brain-derived neurotrophic factor (BDNF), creatine kinase (CK) and myoglobin were determined before (pre) and 0', 30', 60', 240' and 24h after each intervention. RESULTS: Only C+E caused significant increases in levels of CK and myoglobin. BDNF and IL-6 significantly increased after C and C+E, however increases for IL-6 were significantly higher after C+E compared to C. CONCLUSION: The present study showed that superimposed E during cycling might be a useful tool to induce a high local stimulus to skeletal muscle even when performing low to moderate external workloads. This effect might be due the activation of additional muscle fibers and mild eccentric work due to the concomitant activation of agonist and antagonist. However the higher load to skeletal muscle has to be taken into account.
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Ciclismo , Estimulação Elétrica , Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Fator Neurotrófico Derivado do Encéfalo/sangue , Creatina Quinase/sangue , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucina-6/sangue , Masculino , Mioglobina/sangue , Adulto JovemRESUMO
During the last decade, epigenetics became one of the fastest growing research fields in numerous clinical and basic science disciplines. Evidence suggests that chromatin modifications (e.g., histone modifications and DNA methylation) as well as the expression of micro-RNA molecules play a crucial role in the pathogenesis of several cardiovascular diseases. On the one hand, they are involved in the development of general risk factors like chronic inflammation, but on the other hand, epigenetic modifications are conducive to smooth muscle cell, cardiomyocyte, and endothelial progenitor cell proliferation/differentiation as well as to extracellular matrix processing and endothelial function (e.g., endothelial nitric oxide synthase regulation). Therefore, epigenetic medical drugs have gained increased attention and provided the first promising results in the context of cardiovascular malignancies. Beside other lifestyle factors, physical activity and sports essentially contribute to cardiovascular health and regeneration. In this review we focus on recent research proposing physical activity as a potent epigenetic regulator that has the potential to counteract pathophysiological alterations in almost all the aforementioned cardiovascular cells and tissues. As with epigenetic medical drugs, more knowledge about the molecular mechanisms and dose-response relationships of exercise is needed to optimize the outcome of preventive and rehabilitative exercise programs and recommendations.
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Doenças Cardiovasculares/genética , Doenças Cardiovasculares/prevenção & controle , Epigênese Genética/genética , Exercício Físico/fisiologia , Coração/fisiopatologia , Esportes , Adaptação Fisiológica/genética , Humanos , Mecanotransdução Celular , Condicionamento Físico Humano/métodosRESUMO
Exercise has been proven to reduce the risk and progression of various diseases, such as cancer, diabetes and neurodegenerative disorders. Increasing evidence suggests that exercise affects the cytokine profile and changes distribution and function of tumor-competitive immune cells. Initial studies have shown that different exercise interventions are associated with epigenetic modifications in different tissues and cell types, such as muscle, fat, brain and blood. The present investigation examines the effect of an intense endurance run (half marathon) on global epigenetic modifications in natural killer (NK) cells in 14 cancer patients compared to 14 healthy controls. We were able to show that histone acetylation and NKG2D expression, a functional NK cell marker, were elevated for at least 24 h after the run. Thus, this is the first study to present a potential mechanism of how exercise may impact NK cell activity on the subcellular level. Further studies should focus on epigenetic mechanisms and dose-dependent effects of exercise.
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Epigênese Genética , Exercício Físico/fisiologia , Células Matadoras Naturais/metabolismo , Neoplasias/imunologia , Acetilação , Biomarcadores/sangue , Citocinas/metabolismo , Feminino , Histonas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Subfamília K de Receptores Semelhantes a Lectina de Células NK/sangue , Resistência Física/fisiologia , Fatores de Risco , Corrida/fisiologiaRESUMO
The aim of the present study was to compare the effects of active (A) vs. passive (P) recovery during high-intensity interval training on the acute hormonal and metabolic response. Twelve triathletes/cyclists performed four 4 min intervals on a cycle ergometer, either with A- or P-recovery between each bout. Testosterone, hGH, cortisol, VEGF, HGF and MIF were determined pre, 0', 30', 60' and 180' after both interventions. Metabolic perturbations were characterized by lactate, blood gas and spirometric analysis. A-recovery caused significant increases in circulating levels of cortisol, testosterone, T/C ratio, hGH, VEGF and HGF. Transient higher levels were found for cortisol, testosterone, hGH, VEGF, HGF and MIF after A-recovery compared to P-recovery, despite no differences in metabolic perturbations. A-recovery was more demanding from an athlete's point of view. Based on the data of testosterone, hGH and the T/C-ratio, as well as on the data of VEGF and HGF it appears that this kind of exercise protocol with A-recovery phases between the intervals may promote anabolic processes and may lead to pro-angiogenic conditions more than with P-recovery. These data support the findings that also the long term effects of both recovery modes seem to differ, and that both can induce specific adaptations.
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Hormônios/sangue , Educação Física e Treinamento/métodos , Gasometria , Metabolismo Energético , Fator de Crescimento de Hepatócito/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Oxirredutases Intramoleculares/sangue , Ácido Láctico/sangue , Fatores Inibidores da Migração de Macrófagos/sangue , Masculino , Força Muscular/fisiologia , Consumo de Oxigênio , Testosterona/sangue , Fator A de Crescimento do Endotélio Vascular/sangueRESUMO
Patients suffering from type 2 diabetes mellitus (T2DM) often exhibit chronic elevated lactate levels which can promote peripheral insulin resistance by disturbing skeletal muscle insulin-signaling. Monocarboxylate transporter (MCT) proteins transfer lactate molecules through cellular membranes. MCT-1 and MCT-4 are the main protein isoforms expressed in human skeletal muscle, with MCT-1 showing a higher affinity (lower Km) for lactate than MCT-4. T2DM patients have reduced membranous MCT-1 proteins. Consequently, the lactate transport between muscle cells and the circulation as well as within an intracellular lactate shuttle, involving mitochondria (where lactate can be further metabolized), can be negatively affected. This study investigates whether moderate cycling endurance training (3 times per week for 3 months) can change skele-tal muscle MCT contents in T2DM men (n=8, years=56±9, body mass index (BMI)=32±4 kg/m(2)). Protein content analyses (immuno-histochemical stainings) were performed in bio-psies taken from the vastus lateralis muscle. Intracellular MCT-1 proteins were up-regulated (relative increase+89%), while intracellular MCT-4 contents were down-regulated (relative decrease - 41%) following endurance training. Sarcolemmal MCT-1 and MCT-4 did not change. The question of whether the training-induced up-regulation of intracellular MCT-1 leads to an improved lactate transport (and clearance) in T2DM patients requires further research.
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Diabetes Mellitus Tipo 2/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Educação Física e Treinamento , Resistência Física/fisiologia , Simportadores/metabolismo , Idoso , Índice de Massa Corporal , Humanos , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Masculino , Pessoa de Meia-Idade , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , Obesidade/metabolismo , Sobrepeso/metabolismo , Regulação para CimaRESUMO
BACKGROUND: The influences of exercising on cytokine response, fatigue and cardiorespiratory values are important aspects of rehabilitation in persons with multiple sclerosis (PwMS). Exercise performed within these programs is often practised in water but the effects of immersion on PwMS have not been systematically investigated. OBJECTIVE: The objective of this study is to determine differences in cytokine and neurotrophin concentrations, fatigue and cardiorespiratory values in response to 3 week endurance training conducted on a cycle ergometer or an aquatic bike. METHODS: A randomized controlled clinical trial was conducted in 60 MS patients (Expanded Disability Status Scale range 1.0-6.5). Resting serum levels of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), Interleukin-6, soluble receptor of IL-6 and tumor necrosis factor alpha, and concentrations in response to cardiopulmonary exercise test (CPET), fatigue and cardiorespiratory values were determined at entry and discharge. Subjects performed daily 30 minute training at 60% of VO2max. RESULTS: Cytokines and neurotrophins showed no significant differences between groups over the training intervention. Within the water group BDNF resting and post-CPET concentrations (p<0.05) showed a significant increase and NGF tended to increase after the training intervention. Short-term effects on BDNF (CEPT) tended to increase at the start and significantly thereafter (p<0.05). No changes occurred in the land group. Other cytokines and fatigue scores remained unchanged over the training period. Cardiorespiratory values improved significantly over time within both groups. CONCLUSION: This study indicates that aquatic training activates BDNF regulation and can be an effective training method during rehabilitation in PwMS.
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Ciclismo , Citocinas/sangue , Terapia por Exercício , Imersão , Esclerose Múltipla/reabilitação , Fatores de Crescimento Neural/sangue , Adulto , Fator Neurotrófico Derivado do Encéfalo/sangue , Teste de Esforço , Fadiga , Feminino , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Fator de Crescimento Neural/sangue , Resistência Física , Receptores de Interleucina-6/sangue , Resultado do Tratamento , Fator de Necrose Tumoral alfa/sangueRESUMO
In the last years, mainly 2 high-intensity-training (HIT) protocols became common: first, a Wingate-based "all-out" protocol and second, a 4×4 min protocol. However, no direct comparison between these protocols exists, and also a comparison with high-volume-training (HVT) is missing. Therefore, the aim of the present study was to compare these 3 endurance training protocols on metabolic, hormonal, and psychological responses. Twelve subjects performed: 1) HVT [130 min at 55% peak power output (PPO)]; 2) 4×4 min at 95% PPO; 3) 4×30 s all-out. Human growth hormone (hGH), testosterone, and cortisol were determined before (pre) and 0', 30', 60', 180' after each intervention. Metabolic stimuli and perturbations were characterized by lactate, blood gas (pH, BE, HCO3â», pO2, PCO2), and spirometric analysis. Furthermore, changes of the person's perceived physical state were determined. The 4×30 s training caused the highest increases in cortisol and hGH, followed by 4 × 4 min and HVT. Testosterone levels were significantly increased by all 3 exercise protocols. Metabolic stress was highest during and after 4×30 s, followed by 4×4 min and HVT. The 4×30 s training was also the most demanding intervention from an athlete's point of view. In conclusion, the results suggest that 4×30 s and 4×4 min promote anabolic processes more than HVT, due to higher increases of hGH, testosterone, and the T/C ratio. It can be speculated that the acute hormonal increase and the metabolic perturbations might play a positive role in optimizing training adaptation and in eliciting health benefits as it has been shown by previous long term training studies using similar exercise protocols.
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Exercício Físico/fisiologia , Exercício Físico/psicologia , Hormônios/sangue , Metabolismo/fisiologia , Resistência Física/fisiologia , Adulto , Gasometria , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Lactatos/sangue , Motivação , Consumo de Oxigênio , Testosterona/sangueRESUMO
OBJECTIVES: A training intervention comparing resistance exercise with or without whole-body vibration (WBV) was conducted to compare acute and chronic effects on functional and molecular parameters. METHODS: A six-week training intervention was performed including 26 healthy males (26 years, SD=4). Two groups were analyzed in a parallel design performing either resistive exercise (RE, n=13) or resistive vibration exercise (RVE, n=13) training with weekly increasing vibration frequencies (20-40Hz). Resting and exercising blood pressure and heart rate were measured before and after the 6-week intervention. RESULTS: Both training interventions decreased resting systolic blood pressure (P=0.003). Resting diastolic blood pressure was significantly decreased only in the RVE group (P=0.01). Exercising diastolic blood pressure was significantly decreased during the final training (P<0.001) with no additional effect of superimposed vibrations. Resistance exercise with superimposed vibrations evoked back pain to a higher degree than resistance exercise alone when training at frequencies above 30Hz (P<0.01). CONCLUSIONS: These data suggest positive effects of resistance exercise upon cardiovascular health and vascular responsiveness and a further beneficial effect of superimposed vibrations in decreasing resting diastolic blood pressure. Finally, development of back pain may be fostered by superimposed vibrations to high training loads, particularly at higher frequencies.
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Condicionamento Físico Humano/métodos , Treinamento Resistido/métodos , Vibração , Adulto , Pressão Sanguínea/fisiologia , Dieta , Estudos de Viabilidade , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Masculino , Atividade Motora , Esforço Físico/fisiologia , Inquéritos e Questionários , Adulto JovemRESUMO
The present manuscript seeks to discuss methodological aspects regarding the application of the novel unloading orthosis 'HEPHAISTOS' that has been specifically developed to study physiological effects of muscular unloading without altering the impact of gravitational loading. The 'HEPHAISTOS' has been applied in an ambulatory clinical interventional study. During gait, the 'HEPHAISTOS' significantly reduces activation and force production of calf muscles while it completely retains body mass-related force on the tibia. Eleven healthy male subjects participated in the study and followed their normal everyday lives while wearing the orthosis. Several measurement sessions have been performed to investigate the time course of structural and functional adaptations during intervention and recovery. Follow-up measurements were performed for one year after the intervention. In consideration of the experiences of a unique ambulant unloading study, organizational and methodological recommendations are discussed in this manuscript. Activity monitoring data obtained with portable accelerometers reveal unchanged gait activities and good subject compliance throughout the intervention. Moreover, electromyography (EMG) and motion data investigating gait properties on reambulation day are illustrated. These data show that during the initial steps following removal of 'HEPHAISTOS', gait was significantly asynchronous indicating an acutely altered motor control in the unloaded lower leg muscles.
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Marcha/fisiologia , Perna (Membro)/fisiologia , Músculo Esquelético/fisiologia , Aparelhos Ortopédicos , Caminhada/fisiologia , Adulto , Humanos , MasculinoRESUMO
The purpose of the present study was to compare the acute hormonal response of angiogenic regulators to a short-term hypoxic exposure at different altitudes with and without exercise. 7 subjects participated in 5 experimental trials. 2 times subjects stayed in a sedentary position for 90 min at 2000 m or 4000 m, respectively. The same was carried out again in combination with exercise at the same relative intensity (2 mmolâL(-1) of lactate). The fifth trial consisted of 90 min exercise at sea level. Venous blood samples were taken under resting conditions, 0 and 180 min after each condition to determine VEGF, EPO, IL-6, IL-8 and IGF-1 serum concentrations. EPO, VEGF, and IL-8 showed increases only, when hypoxia was combined with exercise. IL-6 was increased after exercise, independent of altitude. IGF-1 showed no changes in any intervention. The present study suggests that short term hypoxic exposure combined with low intensity exercise is able to up-regulate angiogenic regulators, which might be beneficial to induce angiogenesis and to improve endurance performance. However, in some cases high altitudes are needed, or it can be speculated that exercise intensity needs to be increased.
Assuntos
Altitude , Citocinas/sangue , Exercício Físico/fisiologia , Hipóxia/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Fator A de Crescimento do Endotélio Vascular/sangue , Biomarcadores/sangue , Eritropoetina/sangue , Humanos , Hipóxia/etiologia , Hipóxia/fisiopatologia , Interleucina-6/sangue , Interleucina-8/sangue , Masculino , Adulto JovemRESUMO
The immune system plays an important role in mediating exercise responses and adaptations. However, whether fluctuating hormone concentrations across the menstrual cycle may impact these processes remains unknown. The aim of this systematic review with meta-analysis was to compare baseline concentrations as well as exercise-induced changes in immune and inflammatory parameters between menstrual cycle phases. A systematic literature search was conducted according to the PRISMA guidelines using Pubmed/MEDLINE, ISI Web of Science, and SPORTDiscus. Of the 159 studies included in the qualitative synthesis, 110 studies were used for meta-analysis. Due to the designs of the included studies, only the follicular and luteal phase could be compared. The estimated standardized mean differences based on the random-effects model revealed higher numbers of leukocytes (-0.48 [-0.73; -0.23], p < 0.001), monocytes (-0.73 [-1.37; -0.10], p = 0.023), granulocytes (-0.85 [-0.1.48; -0.21], p = 0.009), neutrophils (-0.32 [-0.52; -0.12], p = 0.001), and leptin concentrations (-0.37 [-0.5; -0.23], p = 0.003) in the luteal compared to the follicular phase at rest. Other parameters (adaptive immune cells, cytokines, chemokines, and cell adhesion molecules) showed no systematic baseline differences. Seventeen studies investigated the exercise-induced response of these parameters, providing some indications for a higher pro-inflammatory response in the luteal phase. In conclusion, parameters of innate immunity showed cycle-dependent regulation at rest, while little is known on the exercise responses. Due to a large heterogeneity and a lack of cycle phase standardization among the included studies, future research should focus on comparing at least three distinct hormonal profiles to derive more specific recommendations for exercise prescription.
Assuntos
Fase Folicular , Ciclo Menstrual , Feminino , Humanos , Ciclo Menstrual/fisiologia , Fase Folicular/fisiologia , Exercício Físico/fisiologia , Inflamação , ImunidadeRESUMO
The present study analyzes the oxidative stress situation in the skeletal muscle of overweight/obese men suffering from non-insulin-dependent type 2 diabetes mellitus [T2DM, n=16, years=61±7, body mass index (BMI)=31±4 kg/m(2) ] and BMI-matched non-diabetic male control subjects (CON, n=7, years=53±6, BMI=30±4 kg/m(2) ). Furthermore, it investigates whether physical training can alter the skeletal muscle antioxidative capacity of T2DM patients at rest. Molecule content analyses (immunohistochemical stainings) of 8-iso-prostaglandin-F2α (8-Iso-PGF), superoxide dismutase-2 (SOD2), glutathione peroxidase-1 (GPX1), peroxiredoxin isoforms (PRDX 1-6) and heat-shock-protein-70 (HSP70) were performed in biopsies taken from the vastus lateralis muscle. Under basal conditions, 8-Iso-PGF was significantly decreased in T2DM patients (-35.7%), whereas PRDX2 and PRDX6 were significantly increased relative to CON (+82.6%; +82.3%). Differences were neither observed in SOD2 nor in GPX1 or PRDX1, 3, 4, 5 density. Regular physical activity (moderate endurance or resistance training twice a week for 3 months) did not alter PRDX1, 2, 3, 4, 6 in the skeletal muscle of T2DM patients, but significantly increased SOD2 (+65.9%), GPX1 (+62.4%), PRDX5 (+37.5%), and HSP70 (+48.5%). Overweight/obese men with non-insulin-dependent T2DM exhibit up-regulated cytosolic peroxiredoxin contents relative to BMI-matched controls. Regular training further up-regulates cytosolic and mitochondrial antioxidative enzymes in T2DM patients and improves their cellular protection systems. This may contribute to a retardation of the disease's progression.